From owner-freebsd-stable@FreeBSD.ORG Tue Jul 19 19:38:00 2011 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 0D3AA106566B for ; Tue, 19 Jul 2011 19:38:00 +0000 (UTC) (envelope-from cswiger@mac.com) Received: from asmtpout023.mac.com (asmtpout023.mac.com [17.148.16.98]) by mx1.freebsd.org (Postfix) with ESMTP id E76F98FC0C for ; Tue, 19 Jul 2011 19:37:59 +0000 (UTC) MIME-version: 1.0 Content-transfer-encoding: 7BIT Content-type: text/plain; CHARSET=US-ASCII Received: from cswiger1.apple.com ([17.209.4.71]) by asmtp023.mac.com (Oracle Communications Messaging Exchange Server 7u4-20.01 64bit (built Nov 21 2010)) with ESMTPSA id <0LOL00JQOIIM2110@asmtp023.mac.com> for freebsd-stable@freebsd.org; Tue, 19 Jul 2011 12:37:34 -0700 (PDT) X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:5.4.6813,1.0.211,0.0.0000 definitions=2011-07-19_05:2011-07-19, 2011-07-19, 1970-01-01 signatures=0 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 spamscore=0 ipscore=0 suspectscore=0 phishscore=0 bulkscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx engine=6.0.2-1012030000 definitions=main-1107190158 From: Chuck Swiger In-reply-to: Date: Tue, 19 Jul 2011 12:37:34 -0700 Message-id: <19976EC2-462E-4B2E-AD57-57EC0921A0BF@mac.com> References: <20110718234124.GA5626@icarus.home.lan> To: "freebsd-stable@freebsd.org Stable" X-Mailer: Apple Mail (2.1084) Subject: Re: Status of support for 4KB disk sectors X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 19 Jul 2011 19:38:00 -0000 On Jul 19, 2011, at 12:29 PM, Ivan Voras wrote: >> Is there something in FreeBSD which is preventing you from using the drive's native DEV_BSIZE of 4096 bytes, or is it that the drive claims to have a physical block size of 512 bytes when it is really 4k? > > Nope, "only" that. :-) It's nice to have well-defined problems-- although it's perhaps not so nice when hardware is compelled to lie about its status because of backwards-compatibility (C/H/S vs LBA comes to mind also). > The current state of the matter (i.e. for 9.0) is: > > * The new ATA driver has quirks for certain models of HDDs which have this false advertising (which can be manually triggered by kern.cam.ada.X.quirks=1) which causes the drive to report stripesize of 4k. > > * This information is used in gpart to size & align partitions; it will be used by the new installer > > * Default fragment size for UFS was raised to 4K so it will be aligned by default. Excellent; thanks for the detailed reply. Regards, -- -Chuck